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A section-based queueing-theoretical traffic model for congestion and travel time analysis in networks Sandro Huber
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Agenda Title translation and model introduction Motivating question
Assumptions Key steps Results Questions Sandro Huber
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Title translation and model introduction
Separated by capacity: A section-based … Sandro Huber
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Title translation and model introduction
Separated by capacity: Highway with multiple lines A section-based … Sandro Huber
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Title translation and model introduction
Separated by capacity: Highway with multiple lines Off-ramp, single line A section-based … Sandro Huber
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Title translation and model introduction
Separated by capacity: Highway with multiple lines Off-ramp, single line Main street, multiple lines A section-based … Sandro Huber
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Title translation and model introduction
Points of interest: A section-based … Sandro Huber
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Title translation and model introduction
Points of interest: Measure the flow A section-based … Sandro Huber
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Title translation and model introduction
Points of interest: Measure the flow Reasons for capacity change: A section-based … Sandro Huber
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Title translation and model introduction
Points of interest: Measure the flow Reasons for capacity change: On- or off-ramp A section-based … Sandro Huber
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Title translation and model introduction
Points of interest: Measure the flow Reasons for capacity change: On- or off-ramp Change in number of lines A section-based … Sandro Huber
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Title translation and model introduction
Points of interest: Measure the flow Reasons for capacity change: On- or off-ramp Change in number of lines Change of gradient A section-based … Sandro Huber
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Title translation and model introduction
queueing-theoretical … Sandro Huber
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Title translation and model introduction
traffic model for congestion … Sandro Huber
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Title translation and model introduction
and travel time analysis in networks Sandro Huber
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Title translation and model introduction
Sandro Huber
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Title translation and model introduction
Sandro Huber
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Agenda Title translation and model introduction Motivating question
Assumptions Key steps Results Questions Sandro Huber
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Motivating question What is the expected travel time for a traffic member to go from A to B? Sandro Huber
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Motivating question What is the expected travel time for a traffic member to go from A to B, passing a certain network, including dynamic vehicle density? Sandro Huber
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Agenda Title translation and model introduction
Motivating question Assumptions Key steps Results Questions Sandro Huber
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Assumption 1 Below some critical vehicle density , the relation between the traffic flow and density is linear Sandro Huber
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Assumption 2 Sandro Huber
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Assumption 2 Propagation speed of density variation in
free traffic: the average speed of the cars (30 km/h) Sandro Huber
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Assumption 2 Propagation speed of density variation in
free traffic: the average speed of the cars (30 km/h) congested traffic: Shockwave formulas => … => 20 km/h Sandro Huber
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Assumption 3 The length of the congested area is given by integrating over Sandro Huber
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Assumption 3 The length of the congested area is given by integrating over Sandro Huber
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Assumption 3 The length of the congested area is given by integrating over In english: Sandro Huber
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Assumption 4 The capacity of a congested road = outflow - bottleneck
Sandro Huber
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Assumption 4 The capacity of a congested road = outflow - bottleneck
Less cars can leave the section, but the arrival rate stays the same Sandro Huber
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Assumption 4 The capacity of a congested road = outflow - bottleneck
Less cars can leave the section, but the arrival rate stays the same Congestion grows Sandro Huber
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Assumption 4 The capacity of a congested road = outflow - bottleneck
Less cars can leave the section, but the arrival rate stays the same Congestion grows More cars can leave the section, arrival rate stays the same Sandro Huber
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Assumption 4 The capacity of a congested road = outflow - bottleneck
Less cars can leave the section, but the arrival rate stays the same Congestion grows More cars can leave the section, arrival rate stays the same Congestion gets reduced Sandro Huber
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Agenda Title translation and model introduction
Motivating question Assumptions Key steps Results Questions Sandro Huber
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Key steps We saw: Sandro Huber
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Key steps We saw: Choice of parameters Sandro Huber
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Key steps We saw: Choice of parameters Definition of the model
Sandro Huber
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Key steps We saw: Choice of parameters Definition of the model
Choice of assumptions Sandro Huber
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Key steps Next step: Introduction of road states: Sandro Huber
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Key steps Next step: Introduction of road states: 0: Free traffic
Sandro Huber
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Key steps Next step: Introduction of road states: 0: Free traffic
1: Completely congested road Sandro Huber
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Key steps Next step: Introduction of road states: 0: Free traffic
1: Completely congested road 2: Partially congested road Sandro Huber
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Key steps Final step: Definition of the departure rate Sandro Huber
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Key steps Case: Free traffic here and no congestion in the next section Cars drive through: Sandro Huber
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Key steps Case: Partial or complete congestion here, no in next section Fight through local jam: Assumption 4 => Sandro Huber
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Key steps Case: Next section is completely congested
Its totally dependent on how the traffic rolls in the next section: Sandro Huber
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Agenda Title translation and model introduction
Motivating question Assumptions Key steps Results Questions Sandro Huber
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Results We now can derive a general relationship for the average travel time trough a section: Sandro Huber
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Results We now can derive a general relationship for the average travel time trough a section: When we enter the section i at time t, we will leave this section when the vehicles that are in section i at time t have passed throught it. We can derivate the following formula: Sandro Huber
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Results We now can derive a general relationship for the average travel time trough a section: When we enter the section i at time t, we will leave this section when the vehicles that are in section i at time t have passed throught it. We can derivate the following formula: Sandro Huber
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Results We now can derive a general relationship for the average travel time trough a section: When we enter the section i at time t, we will leave this section when the vehicles that are in section i at time t have passed throught it. We can derivate the following formula: Sandro Huber
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Results Making use of some maths reveals Sandro Huber
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Results Making use of some maths reveals
So, what does this formula mean? Sandro Huber
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Results Making use of some maths reveals
So, what does this formula mean? The travel time increases with time, when the arrival rate at time exceeds the departure time at time (when I want to leave) Sandro Huber
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Results Making use of some maths reveals
So, what does this formula mean? The travel time increases with time, when the arrival rate at time exceeds the departure time at time (when I want to leave) Else, the congestion shrinks, the travel time decreases Sandro Huber
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Results Making use of some maths reveals
So, what does this formula mean? The travel time increases with time, when the arrival rate at time exceeds the departure time at time (when I want to leave) Else, the congestion shrinks, the travel time decreases Fascinating detail: no velocities in the formula! Sandro Huber
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Results Example: Assume you enter the double-lined highway. The arrival rate at 9:30 am is 50 cars/minute. 15 minutes later you arrive at the off-ramp, but just in front of it happened an accident. The police closed one line. Due to this bottleneck the departure rate drops from 50 to 10. Sandro Huber
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Results Example: Assume you enter the double-lined highway. The arrival rate at 9:30 am is 50 cars/minute. 15 minutes later you arrive at the off-ramp, but just in front of it happened an accident. The police closed one line. Due to this bottleneck the departure rate drops from 50 to 10. Apply the formula: Sandro Huber
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Results Example: Assume you enter the double-lined highway. The arrival rate at 9:30 am is 50 cars/minute. 15 minutes later you arrive at the off-ramp, but just in front of it happened an accident. The police closed one line. Due to this bottleneck the departure rate drops from 50 to 10. Apply the formula: Because 4 > 0, the average travel time grows Sandro Huber
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Results So, we did: Sandro Huber
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Results So, we did: Some fancy modelling Sandro Huber
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Results So, we did: Some fancy modelling Some fancy math Sandro Huber
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Results We did: Some fancy modelling… Some fancy math…
Some fancy deductions… Sandro Huber
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Results What fancy stuff can we do with this? Sandro Huber
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Results What fancy stuff can we do with this?
Predict the average travel time for a single vehicle Sandro Huber
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Results What fancy stuff can we do with this?
Predict the average travel time for a single vehicle Predict time loss due to a building site Is a detour needed? Is it even feasible? Sandro Huber
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Results What fancy stuff can we do with this?
Predict the average travel time for a single vehicle Predict time loss due to a building site Is a detour needed? Is it even feasible? Model real traffic situations/systems and simulate solutions/changes on computers Sandro Huber
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Results What fancy stuff can we do with this?
Predict the average travel time for a single vehicle Predict time loss due to a building site Is a detour needed? Is it even feasible? Model real traffic situations/systems and simulate solutions/changes on computers Ect… Sandro Huber
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Agenda Title translation and model introduction
Motivating question Assumptions Key steps Results Questions Sandro Huber
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Thanks for your attention!
Sandro Huber
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Questions Sandro Huber
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